Add GitHub Actions CI workflow for automated testing and building

Co-authored-by: hsluoyz <3787410+hsluoyz@users.noreply.github.com>

Author: Copilot

.github/workflows/ci.yml

@@ -0,0 +1,66 @@
+name: CI
+
+on:
+  push:
+    branches: [ main, master ]
+  pull_request:
+    branches: [ main, master ]
+
+jobs:
+  test:
+    name: Test
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        go-version: ['1.19', '1.20', '1.21']
+    
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Set up Go
+      uses: actions/setup-go@v5
+      with:
+        go-version: ${{ matrix.go-version }}
+
+    - name: Download dependencies
+      run: go mod download
+
+    - name: Verify dependencies
+      run: go mod verify
+
+    - name: Run go vet
+      run: go vet ./...
+
+    - name: Run go fmt
+      run: |
+        if [ "$(gofmt -s -l . | wc -l)" -gt 0 ]; then
+          echo "Please run 'go fmt ./...'"
+          gofmt -s -l .
+          exit 1
+        fi
+
+    - name: Run tests
+      run: go test -v -race -coverprofile=coverage.txt -covermode=atomic ./...
+
+    - name: Upload coverage
+      uses: codecov/codecov-action@v4
+      with:
+        file: ./coverage.txt
+        flags: unittests
+
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Set up Go
+      uses: actions/setup-go@v5
+      with:
+        go-version: '1.21'
+
+    - name: Build
+      run: go build -v ./...